spi: Convert sprd ADI bindings to yaml

Convert spi-sprd-adi.txt to yaml.

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210826091549.2138125-4-zhang.lyra@gmail.com


Signed-off-by: Mark Brown <broonie@kernel.org>